DWC PH Fluctuations

Hi all,

Apologies if this has been covered already - I can't find a post/thread with this issue.

This is my first DWC setup. I'm using a 20gal Rubbermaid tub with three air stones in the bottom. I'm using tap water, no nutes, and a Hanna meter and calibration solution.

My problem is that PH fluctuates wildly. I can adjust the PH down to 5.5, but it will climb back up to 6.5-8 within 24-48 hours. Other than the air stones, there's nothing else in the water, and the water does not touch the net pots.

I have been using white vinegar to lower the PH. Does PH down work better? Any other suggestions on what is causing my PH to climb so rapidly or what I can do to keep the PH in the 5.5-6 range?

Many thanks!

Adding a small amount of nutes will help buffer the PH

Get ph down bro ...I ph my water before it hits the tubs feed and regulate from there...Are there plants in it? No more vinegar.. If nothing else it stinks..LOL U should be feeding them 1/4 strength nutes when the roots hit the water either way.. 300 ppm sounds nice.. bump it to 600 week 2, by week 3 at least in my system they are a foot tall and go to flower...hope that helps.

vinegar breaks down too fast , this causes the wild ph swings....you can use it in an emergency but not for continued use .....if you don't have a hydro shop nearby you can get ph up and down at your local pet store.....just make sure you get the acid base and not citric acid they break down like vinegar.....hope this helps Bro....

Thanks guys. I'll ditch the vinegar and get some ph down. I also added some nutes. I'll keep you posted on the results.

Thanks for the help.

Try putting a regulator on the air hose. I was having the same problem so turned down the amount of air going throught the air stone, and my PH stabilized. To much air brings it up, and to much Co2 brings it down.

I wish I could find my original post where I was asking the very same question, I got some amazing advice/links.

I suppose it could be too much air. I thought you couldn't have too much air, so I bought two Tetra air pumps (dual outlet, each for up to 60gal fishtank). I've unplugged on of the pumps, lowered PH down to 5.8, and will see if that helps overnight.

Thanks for chiming in. If you find that original post, please send it over.

Was it this post?

https://www.rollitup.org/hydroponics-aeroponics/133979-ph-probs-dwc.html

Thats it!
Those guys saved my girls.